I have read an article from Techcrunch, the story talk about two Chinese websites 51tuangou.com and teambuy.com.cn were highlighted, co-ordinate large numbers of consumers interested in buying the same products. People agree on a place and time to meet, then enter the store in crowds of up to 500 people at once. The crowds tell the store owners that they all want to buy, say a TV or a stereo, but everyone wants 10 to 30% off the retail price.